Does your flight deck pre-flight oxygen check detect a system failure?

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A recent report by the AAIB (EW/G2018/12/03) highlights how a pre-flight cockpit oxygen check can fail to detect a failure of the system. In this incident a blockage in the regulator prevented both pilots from getting any oxygen when they were dealing with a suspected de-pressurisation event.

The pre-flight checks may just confirm the system has the correct pressure, but this may not confirm that it will supply any oxygen when it is needed. In response to this incident, the operator has now amended the first flight of the day check to see if the system provides a one second flow of oxygen.  

Could this happen in the aircraft you operate? Following any maintenance, how is the flight deck oxygen system checked? Would, and can your pre-flight checks detect such a failure?

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